Sheet aligning mechanism

ABSTRACT

A sheet aligning mechanism for aligning varied types and weights of sheets which are hand fed thereto includes a continuously rotating feed roll cooperating with a pinch device for urging sheets into both a leading edge aligner and a side edge aligner for leading edge and side edge registration. The feed roll is eccentrically mounted and its clearance with the pinch device is controlled whereby light weight thin sheets are intermittently driven into the aligners. The intermittent sheet drive force prevents sheet buckling and creasing should the operator fail to properly release the sheet. Further, sheet buckling is prevented by the intermittent drive force once the sheet reaches an aligner since the sheet is allowed to restore during the non-drive portion of the feed roll rotation. Once the sheet is properly aligned against both aligners and the utilization device is ready to receive the sheet, an entry gate is actuated and the feed roll forwards the sheet to a sheet take-up device. Thick sheets are continuously driven by the feed roll since they exhibit little propensity toward buckling.

United States Patent 1191 Bleau 1 Sept. 30, 1975 [73] Assignee:International Business Machines Corporation, Armonk, NY.

221 Filed: June 15, 1973 21 Appl. No.: 371,086

Primary Examiner-Evon C. Blunk Assistant E.\'aminer-Bruce H. Stoner, Jr.Att0rne Agent, or Firn1.lohn W. Girvin, Jr.

[ 1 ABSTRACT A sheet aligning mechanism for aligning varied types andweights of sheets which are hand fed thereto includes a continuouslyrotating feed roll cooperating with a pinch device for urging sheetsinto both a leading edge aligner and a side edge aligner for leadingedge and side edge registration. The feed roll is eccentrically mountedand its clearance with the pinch device is controlled whereby lightweight thin sheets are intermittently driven into the aligners. Theintermittent sheet drive force prevents sheet buckling and creasingshould the operator fail to properly release the sheet. Further, sheetbuckling is prevented by the intermittent drive force once the sheetreaches an aligner since the sheet is allowed to restore during thenon-drive portion of the feed roll rotation. Once the sheet is properlyaligned against both aligners and the utilization device is ready toreceive the sheet, an entry gate is actuated and the feed roll forwardsthe sheet to a sheet take-up device. Thick sheets are continuouslydriven by the feed roll since they exhibit little propensity towardbuckling.

5 Claims, 6 Drawing Figures US. Patent Sept. 30,1975 Sheet 1 of23,908,986

US. Patent Sept. 30,1975 Sheet 2 of2 3,908,986

FIG. 4

SHEET ALIGNING MECHANISM BACKGROUND OF THE INVENTION 1. Field 2 Thisinvention relates to sheet handling apparatus and, more particularly, toa document feed apparatus for aligning a document prior to its being fedto a utilization device.

2. Description of the Prior Art Various sheet aligning devices have beenconstructed in the sheet handling art which conventionally employ analigning surface, against which a sheet is registered prior to the sheetbeing forwarded to a utilization device such as a printing press or adocument platen. Such devices often incorporate a second aligningsurface which is perpendicular to the first aligning surface to effectboth front and side registeration of the sheet. One such prior approachutilizes a continuously rotating canted roller cooperating with a pinchdevice to urge the sheet forward and sidewards into perpendicularaligner surfaces. While such a device is satisfactory for feedingrelatively heavy and thick sheets, it has been found that the devicecauses wrinkling and buckling of light weight thin sheets as the sheetis urged into the aligner mechanism. Further, wrinkling and buckling ofthin sheets is also caused when such a device is utilized with sheetsthat are hand fed thereto. This is because the reaction time of variousoperators causes them to hold on to the sheet for an extended periodprior to releasing the sheet to the sheet feed device while the rolleris continuously urging the sheet away.

Various other prior art devices exist for aligning stacks of sheetswithin a pocket or thelike. Such aligning devices often include sheetjoggers operable on the side edges of the sheets in the stack. Thejoggers often include eccentrically mounted rollers and members forperiodically jogging the sheets. However, these devices operate on theside edges of a plurality of sheets in a stack and do not operate on theflat portion of the sheet in co-operation with a pinch device to effectfeeding and aligning thereof.

SUMMARY OF THE INVENTION In order to overcome the foregoing problems ofthe prior art devices and to provide a sheet aligning mechanism foraligning both light weight and heavy weight paper which has been handfed to the aligner, an eccentrically mounted continuously rotating feedroll mounted in cooperative relation with a pinch device is utilized tointermittently supply a driving force to light weight sheets causingthem to be forwarded into an aligner surface. The intermittent sheetdrive prevents sheet bucklingsince the sheet is intermittently releasedas the eccentrically mounted roll rotates thereby allowing the sheet torestore to its unstressed condition. Once the sheet has been properlyaligned against the aligner surfaces and the utilization device is readyto receive the sheet, an entry gate is actuated and the feed roll-pinchdevice cooperate to forward the sheet into a sheet take-up device.Additionally, the clearance between the pinch device and theeccentrically mounted feed roll is controlled so that relatively thickand heavy weight sheets are continuously driven into the alignersurfaces thereby facilitating the rapid aligning and feeding of suchheavy stock. i

Accordingly, it is the principle object of this invention to provide animproved sheet aligning mechanism for aligning varied types and weightsof sheets.

A further object of the invention is to provide a sheet aligner whichreadily aligns light weight sheets which are hand fed thereto.

The foregoing objects, features, and advantages of the invention will beapparent from the following more particular description of the preferredembodiment of the invention as illustrated in the accompanying drawing.

IN THE DRAWING FIG. 1 is a top view of the sheet aligner of the presentinvention.

FIG. 2 is a front view of the sheet forwarding device of the sheetaligner of the present invention;

FIG. 3 is a side view of the sheet forwarding device of the sheetaligner of the present invention.

FIG. 4 is a perspective view of the sheet aligner of the presentinvention.

FIG. 5 is a side view of a portion of the sheet aligner of the presentinvention and of the sheet take-up device.

FIG. 6 is a cross section view of an alternate sheet forwarding deviceof the sheet aligner of the present invention;

Referring now to the drawings, and more particularly to FIG. 1 thereof,a top view of the sheet aligner of the present invention is depicted.A'sheet 11 is placed by hand upon the sheet guide 13 and placed so thatit contacts the feed roll 15 located within an opening of the sheetguide 13. The continuously rotating feed roll 15 is canted causing thesheet to be forwarded in the direction of arrow 17 to a leading edgealigner stop 19 and in the direction of arrow 21 against a side edgealigner stop 23. Once the sheet 11 is squarely positioned against thealigner stops l9 and 23 as depicted, and once the utilization device isready to receive the sheet, the aligner stop 19 and gate fingers 24 aremoved to a position where they no longer intercept the sheet 11. Thesheet 11 is then forwardedby the feed roll 15 to a sheet take-up device(not shown).

The feed roll 15 cooperates with a pinch device to forward the sheet 11in the direction of arrows 17 and 21. The pinch device includes aspherical bearing member 25 which is held by arm 27 above thefeed roll15. As will be described, the feed roll 15 is eccentrically mounted andthe clearance between the feed roll 15 and the spherical bearing member25 is controlled so that the sheet 11 is intermittently driven towardthe leading edge aligner stop 19 and theside' edge aligner stop 23.

Referring now to FIG. 2 of the drawings, a front view of the sheetforwarding device of the sheet aligner is depicted. The sheet forwardingdevice comprises the feed roll 15 and the spherical bearing member 25.The feed roll is eccentrically mounted on shaft 29 and is continuouslydriven by a power source (not shown).

The spherical bearing member 25 rests freely within thecoinically'shaped retainer 31 whereby it is free to move in an upwarddirection. When a sheet (not shown) isfed between the feed roll 15 andthe spherical bearing member 25, the spherical bearing member forms apressure or pinch point with the flat surfaces of vance over the surfaceof the sheet guide 13. As depicted, the feed roll has been rotated toits uppermost position with respect to the spherical bearing member 25and is in contact therewith. The spherical bearing member 25 placesabout five grams of normal force upon the feed roll 13 or upon a thinsheet fed between the feed roll and the bearing member. Thicker sheetsplaced therebetween cause the spherical bearing member 25 to bedisplaced upwards into contact with the spring 32 which supplies anadditional normal force through the spherical bearing member 25 to thethick sheet to facilitate the continuous feeding thereof.

Referring now to FIG. 3 of the drawings, a side view of the sheetforwarding device of the sheet aligner is depicted. As depicted, thefeed roll 15 has been rotated to its lowermost position with respect tothe spherical bearing member 25. The bearing member 25 has fallen to itslowermost position within the retainer 31. Accordingly, a clearancedistance (1, exists between the uppermost surface of the feed roll 15and the lowermost surface of the spherical bearing member 25. Theclearance distance, d, exceeds the thickness of a thin sheet.Accordingly, as feed roll 15 rotates, a thin sheet located between thefeed roll 15 and the spherical bearing member 25 is alternately engagedand disengaged by the sheet forwarding device causing it to beintermittently driven in a sheet forwarding direction.

The surface of the feed roll is made of a material having a coefficientof friction of approximately 0.8 insuring the forwarding of a sheet whenthe sheet is engaged by the sheet forwarding device. Such a feed roll ofapproximately O.625 inches in diameter rotating at approximately 600revolutions per minute rapidly forwards the sheets fed thereby into thealigner stops. Since the feed roll 15 is relatively small compared tothe surface area of a sheet, a sheet such as a sheet of paper can slidefreely thereover when there is no pinch point established such asdepicted in FIG. 3 of the drawings. That is, the lack of a normal forceas applied by the spherical bearing member 25 upon the sheet enables thesheet to move in a restoring direction over the top of the surface ofthe feed roll 15 without undue interference therefrom, As notedheretofore, the distance d is greater than the thickness of a thin sheetbeing fed.

Typical thin sheets of paper materials which can be aligned by the sheetaligner vary from 6 pound onionskin type paper materials having athickness of approximately 0.002 inches to pound bond paper materialshaving a thickness of approximately 0.005 inches. Accordingly, theclearance distance, d, between the low point of the feed roll 15 and theupper surface of the spherical bearing member can be adjusted byloosening the screw 33 and moving the arm 27 relative to the sheet guide13 to be in the range of 0.006 inches to 0.010 inches. Thicker sheetssuch as card stock having a thickness varying between 0.008 inches to0.0l5 inches may then be continuously fed by the sheet forwarding deviceinto the aligner stops of FIG. 1. This material is sufficiently thick sothat it does not buckle when continuously fed by the feed device. Theadditional normal force required to drive such thick sheets is suppliedby the spring 32 which is contacted by the upwardly displaced bearingmember 25. The spring 32 is adjustable with respect to the arm 27 whenthe screw 34 is loosened. 7

Referring now to FIG. 4 of the drawings, a perspective view of the sheetaiigner of the present invention is depicted. As heretofore described, asheet (not shown) is fed over the sheet guide 13 to the leading edgealigner stop 19 and the side edge aligner stop 23 by the eccentricallymounted, canted positioned feed roll 15 and the spherical bearing member25. As also described heretofore, once the sheet is properly registeredagainst the aligner stops, the leading edge aligner stop 19 is moved toa position where it no longer interferes with the advancement of thesheet in the direction of arrow 17.

In order to sense that the sheet is properly registered, the leadingedge aligner stop 19 is pivotally mounted about a shaft 35 supported bythe gate member 36. When the facing surface (not shown) of the leadingedge aligner 19 is contacted by the sheet (not shown), it pivots aboutthe shaft 35 causing the stop member 37 to pivot therewith. In itsnormal position, the stop member 37 prevents the member 39 from pivotingabout the shaft 41. Once the stop member 37 pivots away from the member39, the member 39 is free to pivot about the shaft 41. The member 39 isthusly pivoted when the sheet (not shown) pushes against the side edgealigner stop 23 causing it to push in turn against the member 39. As themember 39 pivots about the shaft 41, it causes the switch 43 to close.The closing of switch 43 enables the energization of the solenoid 45which pivots the sheet gate 36 about the shaft 47 causing the leadingedge aligner stop 19 and the gate fingers 24 to move in a downwarddirection out of the path of the sheet.

Referring now to FIG. 5 of the drawings, a side view of a portion of thesheet aligner and of the sheet takeup means is depicted. As describedheretofore, the sheet 11 is forwarded over the sheet guide 13 to theleading edge aligner stop 19. As also described heretofore, once thesheet is properly registered, the aligner stop 19 and the gate fingers24 are moved to a position where they no longer interfere with thefurther advancement of the sheet 11. The thusly aligned sheet isforwarded by the feed roll 15 of FIG. 1 to a feed belt 51 which deliversthe sheet 11 to the surface of a document platen 53 or the like.

Referring now to FIG. 6 of the drawings, a cross section view of analternate sheet forwarding device of the sheet aligner is depicted. Thesheet forwarding device comprises a pair of eccentrically mounted feedrolls 61, 63 which are mounted on shaft 65 for rotation. The feed rollsrotate to extend through an opening in the sheet guide 13. A pinchdevice 67 is resiliently mounted and is located above the feed rolls.The pinch device 67 has a dimple surface 69 formed therein which restsupon the surface 69 when no sheets are located therebetween. As theeccentrically mounted feed rolls rotate and advance to the positiondepicted, sheets of paper located between the feed roll and the pinchdevice are drivingly forwarded by the rotating feed roll. As the feedrolls rotate from the position depicted, sufficient clearance existsbetween the pinch device 67 and the feed rolls so that a thin sheetlocated therebetween is no longer drivingly engaged thereby even thougha normal force is exerted upon the sheet by the pinch device. This isbecause the normal force is exerted between the drive rolls and does notco-act therewith to provide a sheet forwarding force. Further, since theforce supplied by the dimple 69 against the top surface of a thin sheetis small and applied only at a single point when the rolls are at theirlowermost position, the

sheet can readily restore. It is noted that the sheet is deflected bythe dimple 69 giving the sheet additional column strength in thedirection of feed.

Referring once again to FIG. 1 of the drawings, a sheet 11 insertedbetween the feed roll 15 and the spherical bearing member is forwardedthereby against the side edge aligner stop 23 and the leading edgealigner stop 19. The sheet is forwarded beyond the leading edge alignerstop 19 only after both leading edge and side edge registration havebeen effected. As most often happens, the sheet arrives at one alignerstop prior to reaching the other aligner stop. Additionally, theutilization device may not be ready to receive .a properly registeredsheet. Continued drive force supplied by the feed roll 15 then causesthin sheets of paper to tend to buckle against the surface of thealigner stops. As the eccentrically mounted feed roll 15 rotates to anon-driving position, the sheet restores thereby preventing permanentwrinkling of the sheet by the continued application of a drive force.

As noted heretofore, sheets may be hand fed to the eccentrically mountedfeed roll 15. Should the operator fail to release the sheet or tend topull the sheet away from the feed device, the release of the sheeteffected upon subsequent rotation of the feed roll 13 enables the sheetto restore to an unstressed condition and- /or enables the operator toreadily remove the sheet therefrom.

While the invention has been particularly shown and described withreference to the preferred embodiment thereof, it will be understood bythose skilled in the art that the foregoing and other changes in formand details may be made therein without departing from the spirit andscope of the invention.

What is claimed is:

l. A sheet aligner comprising:

a sheet guide for supporting a sheet;

a first aligner stop positioned adjacent said sheet guide forintercepting a sheet forwarded over the sheet guide;

a second aligner stop positioned approximately perpendicular to saidfirst aligner stop in the plane of sheet travel for intercepting a sheetforwarded over the sheet guide;

a sheet forwarding device for intermittently forwarding a sheet over thesheet guide to the aligner stops, said sheet forwarding device includingan eccentrically mounted roll and a cooperating pinch device, theclearance between the roll and the pinch device allowing alternateengagement and disengagement of a thin sheet fed between the pinchdevice and roll by the roll and pinch device as the roll rotates,

said roll being canted with respect to said first aligner stop and saidsecond aligner stop for simulta neously forwarding a sheet to saidaligner stops;

sensing means for sensing the registration of a sheet against the firstaligner stop and the second aligner stop;

actuable sheet gate means connected to said first aligner stop forpositioning said first aligner stop in a non-intercepting position withrespect to a sheet previously intercepted thereby;

actuator means responsive to the sensing means for actuating the sheetgate means to position the first aligner stop to said non-interceptingposition when a sheet is registered;

sheet take-up means located beyond the first aligner stop in the sheetfeed path for receiving sheets forwarded thereto by the sheet forwardingdevice when the first aligner stop is in the non-intercepting position.

2. The sheet aligner set forth in claim 1 wherein said clearance betweenthe pinch device and driving roll allowing continuous engagement of athick sheet fed between the pinch device and roll by the roll and pinchdevice as the roll rotates.

3. The sheet aligner set forth in claim 1 wherein the pinch deviceincludes a rotatable spherical bearing movable in a directionperpendicular to the sheet feed direction to facilitate the feeding ofsheets of differing thicknesses between the pinch device and the roll.

4. A sheet aligner comprising:

a sheet guide for supporting a sheet;

a first aligner stop positioned adjacent said sheet guide forintercepting a sheet forwarded over the sheet guide;

a second aligner stop positioned approximately perpendicular to saidfirst aligner stop in the plane of sheet travel for intercepting a sheetforwarded over the sheet guide;

a sheet forwarding device for intermittently forwarding a sheet over thesheet guide to the aligner stops, said sheet forwarding device includingan eccentrically mounted roll positioned canted with respect to each ofsaid aligner stops for simultaneously forwarding a sheet toward each ofsaid aligner stops and a cooperating pinch device, the roll and thepinch device providing an intermittent sheet forwarding drive force tobe applied to a sheet fed between the pinch device and roll by the rolland pinch device as the roll rotates;

sensing means for sensing the registration of a sheet against the firstaligner stop and the second aligner stop;

actuable sheet gate means connected to said first aligner stop forpositioning said first aligner stop in a non-intercepting position withrespect to a sheet previously intercepted thereby;

actuator means responsive to the sensing means for actuating the sheetgate means to position the first aligner stop to said non-interceptingposition when a sheet is registered;

sheet take-up means located beyond the first aligner stop in the sheetfeed path for receiving sheets forwarded thereto by the sheet forwardingdevice when the first aligner stop is in the non-intercepting position.

5. The sheet aligner set forth in claim 4 wherein the pinch deviceincludes a rotatable spherical bearing movable in a directionperpendicular to the sheet feed direction to facilitate the feeding ofsheets of differing thicknesses between the pinch device and the roll.

1. A sheet aligner comprising: a sheet guide for supporting a sheet; afirst aligner stop positioned adjacent said sheet guide for interceptinga sheet forwarded over the sheet guide; a second aligner stop positionedapproximately perpendicular to said first aligner stop in the plane ofsheet travel for intercepting a sheet forwarded over the sheet guide; asheet forwarding device for intermittently forwarding a sheet over thesheet guide to the aligner stops, said sheet forwarding device includingan eccentrically mounted roll and a cooperating pinch device, theclearance between the roll and the pinch device allowing alternateengagement and disengagement of a thin sheet fed between the pinchdevice and roll by the roll and pinch device as the roll rotates, saidroll being canted with respect to said first aligner stop and saidsecond aligner stop for simultaneously forwarding a sheet to saidaligner stops; sensing means for sensing the registration of a sheetagainst the first aligner stop and the second aligner stop; actuablesheet gate means connected to said first aligner stop for positioningsaid first aligner stop in a non-intercepting position with respect to asheet previously intercepted thereby; actuator means responsive to thesensing means for actuating the sheet gate means to position the firstaligner stop to said non-intercepting position when a sheet isregistered; sheet take-up means located beyond the first aligner stop inthe sheet feed path for receiving sheets forwarded thereto by the sheetforwarding device when the first aligner stop is in the non-interceptingposition.
 2. The sheet aligner set forth in claim 1 wherein saidclearance between the pinch device and driving roll allowing continuousengagement of a thick sheet fed between the pinch device and roll by theroll and pinch device as the roll rotates.
 3. The sheet aligner setforth in claim 1 wherein the pinch device includes a rotatable sphericalbearing movable in a direction perpendicular to the sheet feed directionto facilitate the feeding of sheets of differing thicknesses between thepinch device and the roll.
 4. A sheet aligner comprising: a sheet guidefor supporting a sheet; a first aligner stop positioned adjacent saidsheet guide for intercepting a sheet forwarded over the sheet guide; asecond aligner stop positioned approximately perpendicular to said firstaligner stop in the plane of sheet travel for intercepting a sheetforwarded over the sheet guide; a sheet forwarding device forintermittently forwarding a sheet over the sheet guide to the alignerstops, said sheet forwarding device including an eccentrically mountedroll positioned canted with respect to each of said aligner stops forsimultaneously forwardIng a sheet toward each of said aligner stops anda cooperating pinch device, the roll and the pinch device providing anintermittent sheet forwarding drive force to be applied to a sheet fedbetween the pinch device and roll by the roll and pinch device as theroll rotates; sensing means for sensing the registration of a sheetagainst the first aligner stop and the second aligner stop; actuablesheet gate means connected to said first aligner stop for positioningsaid first aligner stop in a non-intercepting position with respect to asheet previously intercepted thereby; actuator means responsive to thesensing means for actuating the sheet gate means to position the firstaligner stop to said non-intercepting position when a sheet isregistered; sheet take-up means located beyond the first aligner stop inthe sheet feed path for receiving sheets forwarded thereto by the sheetforwarding device when the first aligner stop is in the non-interceptingposition.
 5. The sheet aligner set forth in claim 4 wherein the pinchdevice includes a rotatable spherical bearing movable in a directionperpendicular to the sheet feed direction to facilitate the feeding ofsheets of differing thicknesses between the pinch device and the roll.